Don't show debug messages when not debugging
The "DEBUG" messages from glib (g_debug) appears even when running with the "Run" button, which prints a lot of useless things when you are just trying to program. This makes it difficult to see messages that you might print to see the run path of the program, when X function is called and with what, etc. So I propose to only show "DEBUG" messages when actually using "Run with debugger". I think it sets G_MESSAGES_DEBUG to some value including "debug".